Hidden upside to Sydney's driest eight months in 50 years

By Peter Hannam

31 August 2018 — 4:25pm

Sydney's driest start to the year in half a century shows little sign of ending but the lack of rain may have an upside for hay fever sufferers.

Paultry rainfall of 7.8 millimetres in August followed 11.2 millimetres in July, making it the smallest tally for those two months in 23 years, Brett Dutschke, a senior meteorologist with Weatherzone said.

'Yellow dandruff': Ruby Shevlin and her dog Raffi with a wattle in full bloom at their Chatswood home ahead of National Wattle Day on September 1.

Photo: Jessica Hromas

That compares with an average rainfall of 176.7 millimetres for those two months. So far this year, Sydney has collected 511 millimetres, or just over half the normal level of rain, making it the driest January-August since 1968, he said.

Two rain-bearing systems may bring some relief to parched regions of the state, including Sydney, next week. Moist easterly winds, more typical of spring, followed by a cold front with a wintry edge could bring falls of as much as 20 millimetres to the city, according to Bureau of Meteorology forecasts.

A taste of spring should certainly be in the air on Saturday, the official start of spring, with a top of 21 degrees predicted - or a couple of degrees above the September daytime average.

Sydneysiders, though, will have to wait until the end of next week for the next bout of warmth. Cloudier conditions, though, should at least snap the run of cold nights for most of the city.

Rain on the plain: Much needed rain fell on Bathurst on Friday.

Photo: David Porter

Pollen watch

The arrival of spring, including National Wattle Day - celebrated nationally since 1992 - is often the time when hay fever sufferers start raiding the bathroom cabinet for anti-inflammatory nasal sprays and other anti-allergy medicine.

Ruby Shevlin is someone who watches out for the blossoming of the "beautiful native tree" that flowers every year at her Chatswood home.

"The wattle makes me look like I've got yellow dandruff, so I can understand why people don't want it in their yard," Ms Shevlin said. "Our dog brings it in and mum puts it in a vase - despite me being allergic."

Jane Rimmer, an associate professor at the University of Sydney's medicine faculty, said people often blame wattle for their hay fever because they can see the pollen. However, it is usually the smaller particles, particularly from exotic rye grass, that trigger allergic reactions.

"Allergies to native plants are not that common," Professor Rimmer said, adding that grasses and weeds rather than trees are probably the dominant sources of allergens in NSW.

The trigger for high reactions is often thunderstorms, which have the effect of breaking pollen into smaller particles that can more easily enter nasal passages.

The peak season for grass-related pollen is typically October and November in Sydney, she said.

Should this year's dry spell continue, hay fever sufferers may be in for a relatively benign season.

"My guess is that it may be a lower pollen season this year," Professor Rimmer said.